The present invention relates to a spectrophotometer suitable especially for measurement in a near infrared wavelength region.
In the conventional spectrophotometer, a lead sulfide (PbS) sensor is used as a sensor for the near infrared region under the room temperature.
In the above-mentioned conventional spectrophotometer, the sensitivity of the sensor is low and the S/N (signal-to-noise) ratio thereof is also low in the near infrared region. Further, there is a problem that the sensitivity and response speed of the sensor element for the near infrared region is deteriorated under use at the room temperature.